Ultrahigh mobility and efficient charge injection in monolayer organic thin-film transistors on boron nitride
Publication in refereed journal


摘要Organic thin-film transistors (OTFTs) with high mobility and low contact resistance have been actively pursued as building blocks for low-cost organic electronics. In conventional solution-processed or vacuum-deposited OTFTs, due to interfacial defects and traps, the organic film has to reach a certain thickness for efficient charge transport. Using an ultimate monolayer of 2,7-dioctyl[1] benzothieno[3,2-b][1] benzothiophene (C8-BTBT) molecules as an OTFT channel, we demonstrate remarkable electrical characteristics, including intrinsic hole mobility over 30 cm(2)/Vs, Ohmic contact with 100 Omega circle cm resistance, and band-like transport down to 150 K. Compared to conventional OTFTs, the main advantage of a monolayer channel is the direct, nondisruptive contact between the charge transport layer and metal leads, a feature that is vital for achieving low contact resistance and current saturation voltage. On the other hand, bilayer and thicker C8-BTBT OTFTs exhibit strong Schottky contact and much higher contact resistance but can be improved by inserting a doped graphene buffer layer. Our results suggest that highly crystalline molecular monolayers are promising form factors to build high-performance OTFTs and investigate device physics. They also allow us to precisely model how the molecular packing changes the transport and contact properties.
著者D. W. He, J. Qiao, L. Zhang, J. Wang, T. Lan, J. Qian, Y. Li, Y. Shi, Y. Chai, W. Lan, L. K. Ono, Y. Qi, J. B. Xu, W. Ji, X. Wang
期刊名稱Science Advances
頁次1 - 9

上次更新時間 2020-25-10 於 03:10